The present invention relates generally to fiber optic based sensors. Fiber optic sensors have been designed to detect a wide number of phenomena and are free from the problems of radiating electromagnetic fields (EMF) and are not susceptible to noise cause by electromagnetic interference (EMI). Further, fiber optic sensors can be used in a number of environments including high temperature and toxic environments with little or no degradation in performance.
Fiber optic based sensors are designed to detect one, possibly two, physical phenomena and the prior art sensors cannot be substantially modified or changed once constructed. This creates a problem in the manufacturability of a wide range of fiber optic sensors in that each type of sensor is made from substantially different components using substantially different fabrication and/or construction methods resulting in higher costs as compared to sensors based on electrical detection methods.
Prior art fiber optic sensors are limited to the practice of a specific optical detection method and a specific transduction mechanism that cannot be changed once the sensor is fabricated or constructed. This means that the end user has to use the detection method the fiber optic was designed for. The majority of the detection methods used simply are not required because the sensitivity is not required for the particular uses of the fiber optic sensors. For example, if a sensor is interrogated using interfermetric detection with light polarization detection equipment, the cost is very high. However, an interferometric technique may not be required and a less expensive interrogation technique, such as multifiber intensity detection, may be sufficient. The sensor described in this document allows the user to pick and select the detection system that is sufficient for said users needs.
It is therefore desirable to provide a modular fiber optic sensor that can be easily modified to detect a wide range of phenomena while also allowing the user to choose the detection method used to interrogate the sensor.